The production of recombinant proteins for biopharmaceutical applications typically involves the use of cell cultures having variable protein expression efficiencies. Advances in technologies for gene mapping, bio-imaging, and whole proteome analysis provide unique opportunities to understand many of the bottlenecks associated with the use of cell cultures for large-scale production of recombinant proteins. Numerous presentations at recent conferences (IBC-Antibody Development and Production, San Diego, Mar. 12-14, 2008), as well as publications in peer-reviewed journals (Gupta, P. and K. H. Lee (2007), “Genomics and proteomics in process development: opportunities and challenges” Trends Biotechnol 25(7): 324-30.) have demonstrated the utility of such technologies in the biopharmaceutical industry. The objectives for many of these studies include improving cell productivity, improving cell culture survival and proliferation, as well as introducing rapid and reliable techniques for the selection of high producing cell lines and real-time monitoring of the viability and physiology of the cells.
Even in light of the above-described advances, there remains a need in the art to identify biomarkers that correlate with high efficiency protein expression, particularly in the context of cell culture processes used for commercially produced recombinant bio-therapeutics. The instant invention addresses that need by providing secretory protein biomarkers that correlate with high efficiency protein expression